Sunday, 11 July 2010

Decoction vs Infusion

The two classic mashing systems, head to head. When Harp brewers took a scientific approach. Consecutive gyles of the same beer, one decoction, one infusion.

Seems a fairl test to me. Want to see the resulyts? Of course you do.

Both beers were brewed at Park Street, the Barclay Perkins Lager brewery.

Given they found that "the analytical characteristics of the two beers were very similar", it makes you wonder if they stuck with decoction mashing. I should maybe take another look at the Lager brewing logs.

There's one significant characteristic they didn't take into account: flavour. It clearly wasn't a consideration. Isn't that a surprise.

There could be any number of reasons for this test. How did Barclay Perkins mash their own lager, and was it still current knowledge at the brewery? Perhaps Guinness had told them to do a decoction mash, and they were trying to figure out whether Guinness would notice if they used an infusion mash instead.

That was interesting reading, and such a pity that the flavour aspect was entirely ignored.

Some brewers I know locally use an infusion mash for their lager as well as their ale, arguing that the malts they use are sufficiently modified so as to make decoction redundant, others insist that decoction is essential for keeping with the style guidelines.

While I would not want to comment on the science side of the argument, I know which lager from the local breweries I prefer. The one which is made with a double decoction mash.